This repost was presented at Fronties in Computational Astrophysics Conference (Lyon, France, 11-15 October, 2010). I give brief and light introduction to CUDA architecture and it's benefits for scientific HPC. Also a brief description about KIPT in-house package for N-body simulations is given. This talk with minor differences was also presented at seminars in Institute for Single Crystals (Kharkov) and Kharkov Institute of Physics and Technology.